1. Field of the Invention
The present invention relates to a brushless DC motor employed with a refrigerant compressor or the like.
2. Description of Related Art
There is a prior art regarding a brushless DC motor that has been disclosed in Japanese Unexamined Patent Publication No. 8-237897.
As the same type of the brushless DC motor disclosed in the publication, there is one shown in FIG. 6 that includes a sheet-like insulating constituent 51, an iron core 52, teeth 53 of the iron core, and a slot aperture 54 between teeth. The insulating constituent, which is formed by folding beforehand, is disposed at the slot or the slot aperture 54, then a winding is provided on the insulating constituent to assemble the brushless DC motor.
If the winding is, for example, automatically wound by a machine around the iron core of the brushless DC motor as described above, insufficiently folded ends 55 of the insulating constituent 51 are positioned at a center of the slot aperture 54 causes a nozzle 60 for wrapping the winding to push the ends of the insulating constituent. This has been posing a danger of the insulating constituent to be dislocated or broken (refer to FIG. 6B). The dislocated or broken insulating constituent has been leading to a likelihood of an insulation failure.
Accordingly, it is an object of the present invention to provide a brushless DC motor capable of improving productivity and minimizing chances of insulation failures.
To this end, according to one aspect of the present invention, there is provided a brushless DC motor having a winding directly provided on a tooth of a stator, comprising; a plate-like insulating constituent disposed at the tooth; and a slant portion provided on an end portion of the insulating constituent positioned between teeth such that the slant portion is inclined with respect to a central line between the teeth.
The insulating constituent is formed to be symmetrical with respect to the central line between the teeth.
A coil end or the coil end and an outgoing line are bound using a polyester thread.
A permanent magnet provided in a rotor of the brushless DC motor employs a rare earth material.
In a distal end portion of a tooth of a stator core of a concentrated winding type motor, a cut portion is formed on an inner-diameter tooth portion excluding a tooth body so that the cut portion extends as far as an aperture.
In the distal end portion of a tooth of the stator core of the concentrated winding type motor, the cut portion is provided on one side of the inner-diameter tooth portion excluding the tooth body so that the cut portion extends as far as the aperture.
In the distal end portion of a tooth of the stator core of the concentrated winding type motor, cut portions are provided on both sides of the inner-diameter tooth portion excluding the tooth body so that the cut portions extend as far as the aperture.
In the distal end portion of a tooth of the stator core of the concentrated winding type motor, a hole is provided in the vicinity of a slot aperture in a distal end portion excluding the tooth body.
In the distal end portion of a tooth of the stator core of the concentrated winding type motor, a groove is provided in the vicinity of a slot aperture in the distal end portion excluding the tooth body.
In the distal end portion of a tooth of the stator core of the concentrated winding type motor, a notch is provided so as to substantially increase a width of a gap between opposing tooth distal end portions.
The stator core of the concentrated winding type motor has a jig inserting hole for processing an outgoing line that is opened in an axial direction of the motor on an outer periphery side at a center of a stator tooth so that a relationship represented by Hxe2x89xa7T/2 is established when a distance between a tooth and a corner at a slot bottom is denoted by H and a mean tooth width is denoted by T. An outgoing line of a drive coil is secured to a junction insert that is fixedly inserted in the jig inserting hole.
The stator core of the concentrated winding type motor has a jig inserting hole for processing an outgoing line that has been opened in an axial direction of the motor on an outer periphery side at a center of a stator tooth so that a relationship represented by Hxe2x89xa7T/2 is established when a distance between a tooth and a corner at a slot bottom is denoted by H and a mean tooth width is denoted by T. An outgoing line of a drive coil is secured to a junction insert that is fixedly inserted in the jig inserting hole. The jig inserting holes and the junction inserts are provided on an arbitrary number of stator teeth.
The stator core of the concentrated winding type motor has: a jig inserting hole for processing an outgoing line that has been opened in an axial direction of the motor on an outer periphery side at a center of a stator tooth so that a relationship represented by Hxe2x89xa7T/2 is established when a distance between a tooth and a corner at a slot bottom is denoted by H and a mean tooth width is denoted by T; and a resinous insulating jig fixedly inserted in the jig inserting hole. An inserting shaft of the junction insert has a device for preventing slippage in one direction, and an outgoing line of the drive coil is secured to a junction insert composed of an annular means for securing the outgoing line that has a cut in a part of its top portion.
A tooth distal end of the stator core of the concentrated winding type motor is constructed such that a distance T between a line A connecting right and left distal end points A and Axe2x80x2 of a tooth distal end portion of the stator core and a tangent B of an inner diameter of tooth is Txe2x89xa70 (closer to an outer diameter of the stator).
In the stator of the concentrated winding type motor, a lead connection and a neutral point of the drive coil are buried in a slot by making use of a space of the slot of the stator core.
In the stator of the concentrated winding type motor, the lead connection and a neutral point of the drive coil is buried in the slot by making use of a space secured in the slot of the stator core for operating a needle of a winding nozzle when winding the drive coil.
In the stator of the concentrated winding type motor, the drive coil is wound with a spacer provided between an end surface of a stator tooth and the drive coil so as to reduce stress applied by the coil to slot insulating paper when winding the coil around a tooth of the stator core.
In the stator of the concentrated winding type motor, the drive coil is wound by providing a spacer, which allows a height H to secure an insulation distance, between the end surface of the stator tooth and the drive coil so as to reduce stress applied by the coil to the slot insulating paper when winding the coil around a tooth of the stator core.
In the stator of the concentrated winding type motor, the drive coil is wound by providing a spacer, which has a shape matching a desired shape of a coil end, between the end surface of the stator tooth and the drive coil so as to reduce stress applied by the coil to the slot insulating paper when winding the coil around a tooth of the stator core.
In the stator of the concentrated winding type motor, plate-like slot insulating paper of 0.2 mm to 0.5 mm is disposed on an inner edge of the slot of the stator core, and a portion of the insulating paper that projects from an end surface of the stator is folded a plural number of times toward a tooth of the stator and welded by heating.
In the stator of the concentrated winding type motor, plate-like slot insulating paper of 0.2 mm to 0.5 mm is disposed on an inner edge of the slot of the stator core, and a portion of the insulating paper that projects from an end surface of the stator is folded toward a tooth of the stator, and a reinforcing insulator is provided between the end surface of the stator and the insulating paper.
In the stator of the concentrated winding type motor, the stator core is provided with a skew that is 7.5xc2x15 degrees with respect to a shaft of the stator.
In a rotor of the concentrated winding type motor, a rotor core is provided with a skew that is 7.5xc2x15 degrees with respect to a shaft of the rotor.
In the concentrated winding type motor,-both the stator core and the rotor core are provided with skews, skew angles of the two having a relative angle of 7.5xc2x15 degrees.
In the stator of the concentrated winding type motor, a tooth of the stator core is shaped so that a portion on the stator inner diameter side is wider than a slot bottom.
In the rotor of the concentrated winding type motor, a core cut of an outer peripheral portion of a rotor having a magnet inserted and buried is formed so that its shape is different in upper and lower portions thereof in a laminating direction of a lamination thickness of the rotor core.
In the rotor of the concentrated winding type motor, a core cut of an outer peripheral portion of a rotor having a magnet inserted and buried is formed so that its shape is different in upper and lower portions thereof in a laminating direction of a lamination thickness of the rotor core. Furthermore, the inserted magnetic is of the same magnet shared by the upper and lower portions having cuts of different shapes in the laminating direction, or is composed separate magnets for the upper and lower portions.
In the rotor of the concentrated winding type motor, a core cut of an outer peripheral portion of a rotor having a magnet inserted and buried is formed so that its shape is different in upper and lower portions thereof in a laminating direction of a lamination thickness of the rotor core. Furthermore, the inserted magnetic employs separate magnets for the upper and lower portions having different cut shapes in the laminating direction, and the magnets inserted in the outer peripheral portions having different shapes are shifted in a radial direction.
In the stator of the concentrated winding type motor, a plate-like slot insulating paper is disposed on an inner edge of a slot of the stator core, and an aperture width Y of an end surface of the insulating paper that opposes an aperture of the slot is smaller than a width X of a gap between distal end portions of stator teeth.
In the stator of the concentrated winding type motor, a plate-like slot insulating paper is disposed on an inner edge of a slot of the stator core, and the end surface of the insulating paper is extended along the stator tooth distal end portion that opposes an aperture of the slot.
In the stator core of the concentrated winding type motor, a distance between an intersection X and an intersection Y, which are obtained when a bottom point P of a tooth of a stator slot and a bottom point E of a slot are placed on extended perpendiculars that intersect a straight line extending from a center of a stator and passing a center of the tooth, is set so that the bottom point E of the slot lies within a range of xe2x88x922 mm to +5 mm from the bottom point P of the tooth providing a reference point.
The stator cores are laminated and bound at a caulking spot disposed in a range of an extension of a stator tooth width X in a direction of an outer diameter.
The brushless DC motor and a compressor unit driven by the brushless DC motor are installed in a case to constitute a refrigerant compressor.
An HC type refrigerant is employed as a medium for the compressor.